1. Field of the Invention
The present invention relates to a relay station, a base station, a relay method, a transmission method, and a computer readable medium thereof for use in a multi-hop network. More specifically, the present invention relates to a relay station, a base station, a relay method, a transmission method, and a computer readable medium thereof for use in a multi-hop network based on the non-transparent framework.
2. Descriptions of the Related Art
In conventional one-hop and frame-based network under centralized control and scheduling, the base station (BS) is responsible for the control of radio resource utilization. After the BS finished arrangement of the resource allocation of a frame, it informs all subordinated stations, attached to it, by broadcasting messages called downlink map(DL-MAP) and uplink map (UL-MAP) containing multiple information elements (IEs) to them. From the MAP IEs, the stations other than BS can obtain the information of downlink receptions and uplink transmissions.
For a multi-hop network, there should be MAP IEs to inform the relay stations (RSs) to serve their subordinated stations (RS/MS) about downstream transmissions and upstream receptions for data forwarding. However, in the MAP IEs relay process, the BS/RS only generates a frame the MAP IEs for the subordinated stations (RS/MS) which are located within the coverage of the BS/RS. In other words, the BS/RS does not generate the MAP-IEs, which are needed by all stations in the multi-hop network, in a frame. The RS must receive the frame generated by the superordinate station (BS/RS), parse the frame, generate the MAP-IEs needed by the subordinated station, and generate the next frame for the subordinated station by packaging the MAP-IEs generated by the RS. A frame contains management messages and relaying data.
In addition, in conventional multi-hop network, for downstream transmissions and upstream receptions for data forwarding, there are two ways generally to achieve: the RS building a routing table for relaying data and attaching an additional header in the relayed data. However, the conventional data forwarding has the following defects: increasing the loading of network and the relay station.
In summary, how to achieve data forwarding and not increase additional loading in multi-hop network or the relay station is still an object for the industry to endeavor.